Development of scenarios for carbon capture and storage ECCO - European value chain for CO2

AbstractThis paper describes the process of scenario development under ECCO and presents six scenarios resulting from that process. The main objective of ECCO is to facilitate robust strategic decision making regarding early and future deployment of CO2 value chains. The ECCO project strategy is based on critical evaluation of several case studies that will enlighten various aspects of CCS and point out the most promising CO2 chain alternatives. Scenarios in ECCO help to define the background for the case studies. They describe the alternative future(s) in terms of political environment, public opinion, regulatory framework, technology and infrastructure development, and global economical situation

Crossed-Beams and Theoretical Studies of Hyperthermal Reactions of O(\u3csup\u3e3\u3c/sup\u3eP) with HCl†

The reaction of O(3 P) with HCl at hyperthermal collision energies (45-116 kcal mol-1 ) has been investigated with crossed-molecular beams experiments and direct dynamics quasi-classical trajectory calculations. The reaction may proceed by two primary pathways, (1) H-atom abstraction to produce OH and Cl and (2) H-atom elimination to produce H and ClO. The H-atom abstraction reaction follows a stripping mechanism, in which the reagent O atom approaches the HCl molecule at large impact parameters and the OH product is scattered in the forward direction, defined as the initial direction of the reagent O atoms. The H-atom elimination reaction is highly endoergic and requires low-impact-parameter collisions. The excitation function for ClO increases from a threshold near 45 kcal mol-1 to a maximum around 115 kcal mol-1 and then begins to decrease when the ClO product can be formed with sufficient internal energy to undergo secondary dissociation. At collision energies slightly above threshold for H-atom elimination, the ClO product scatters primarily in the backward direction, but as the collision energy increases, the fraction of these products that scatter in the forward and sideways directions increases. The dependence of the angular distribution of ClO on collision energy is a result of the differences in collision geometry. Collisions where the H atom on HCl is oriented away from the incoming reagent O atom lead to backward-scattered ClO and those where the H atom is oriented toward the incoming O atom lead to forward-scattered ClO. The latter trajectories do not follow the minimum energy path and involve larger translational energy release. Therefore, they become dominant at higher collision energies because they lead to lower internal energies and more stable ClO products. The H-atom abstraction and elimination reactions have comparable cross sections for hyperthermal O(3 P) + HCl collisions

PHOTODISSOCIATION DYNAMICS OF THE PHENYL RADICAL VIA PHOTOFRAGMENT TRANSLATIONAL SPECTROSCOPY

Author Institution: College of Chemistry, University of California, Berkeley, California 94720, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USAPhotofragment translational spectroscopy was used to study the photodissociation dynamics of the phenyl radical at 193 and 248 nm. Time of flight data collected for the C$_6$H$_4$, C$_4$H$_3$, and C$_2$H$_2$ photofragments show the presence of two decomposition channels. The only C$_6$H$_5$ decomposition channel observed at 248 nm corresponds to C ??H bond fission from the cyclic radical producing $ortho$-benzyne. The translational energy distribution peaks at 0 $kcal/mol$ and is consistent with no exit barrier for the H loss process. At 193 nm photodissociation, however, H loss was observed to be the minor channel, while the major decomposition pathway corresponds with decyclization of the C$_6$H$_5$ radical and subsequent fragmentation to $n$-C$_4$H$_3$ and C$_2$H$_2$. These two momentum matched photofragments have a translational energy distribution that peaks around 9 $kcal/mol$, indicative of a process that proceeds through a tighter transition state. Previous theoretical work on the unimolecular decomposition of the phenyl radical \textbf{1997}, 101, 6790.} predicts a second H loss process that occurs after C$_6$H$_5$ decyclization resulting in the linear C$_6$H$_4$ photofragment. This channel cannot be unambiguously discerned from the C$_6$H$_4$$^+$ time of flight data, but is believed to take place since decyclization is observed

Carbon chain analysis on a coal IGCC - CCS system with flexible multi-products

&nbsp;A carbon chain analysis is applied to assess a complex energy conversion system with CO2 capture and storage (CCS). A coal integrated gasification combined cycle, with CCS, which co-produces electricity and liquid fuels (IGCC-LF-CCS) is taken as a case study. A process simulation method is used to estimate the technological data, and balance the heat and electricity for the whole system. Carbon and energy flows are calculated to evaluate the mass conversion efficiency and the energy efficiency. The results show that in the case in which one third of the coal is allotted to synthesize liquid fuels, globally 60% carbon is captured for storage, 19% transferred to liquid fuels, 19% emitted to the atmosphere, while the remaining carbon is discharged as waste. For the energy flow, 28.1% of total higher heating value of coal is converted into the liquid fuels. The net electricity efficiency is 20.7% accounting for the power demands by air separation, CO2 capture and compression. Three scenarios with different ratio of resource to produce electricity and liquid fuels with or without CCS have been studied. This work will provide useful information for the coal utilization with CCS in a carbon-constrained world. (C) 2012 Elsevier B.V. All rights reserved.</span

Integrated Techno-economic and Environmental Assessment of an Amine-based Capture

AbstractA systematic methodology for integrated techno-economic and environmental assessment of CCS value chains is presented and applied to assess the impact of the CO2 concentration on an amine-based post-combustion CO2 capture process. In this methodology, the technical assessment, economic evaluation, and environmental assessment (focusing on the global warming effect) are integrated in order to avoid the unilateral understandings obtained when these assessments are performed separately. Seven cases with CO2 concentrations between 2.5 and 20.5% (mol) are investigated in terms of energy consumptions, the overall costs, as well as the climate impact of the capture process. The process simulation is performed with Aspen Plus®, and the techno-economic evaluation using Aspen Process Economic Analyzer®. A hybrid life cycle assessment approach is used to estimate the climate impact of the capture based on the results of techno-economic assessment. The CO2 avoided capture cost, which reflects both the techno- economic and environmental performances, is used to assess the comprehensive impact of the CO2 concentration on the capture process